Anthony, can you please tell me the difference between nitrification and denitrification? I know I have links that explain this somewhere, but I am feeling so yucky after being out in the cold today that I can't think straight. For the life of me I can't remember what denitrification is...thanks!

Anthony, can you please tell me the difference between nitrification and denitrification? I know I have links that explain this somewhere, but I am feeling so yucky after being out in the cold today that I can't think straight. For the life of me I can't remember what denitrification is...thanks!

PS - congrats again on moderator, in case people haven't noticed!

Nitrification is the process of converting ammonia to nitrates, and requires an aerobic environment.

Denitrification is the reverse process; converting from nitrates to nitrogen gas.

That is the general gist of things. There are some bacteria that can carry out more/less steps of each pathway and/or carry the process further (i.e. all the way to nitrogen gas rather than just nitrite, etc).

Also, thank you for your kind words. I look forward to making TPT an enjoyable experience for everyone.

I just looked up the matrix product description on seachem's website, and they claim:

"...These macropores are ideally sized for the support of nitrifying and denitrifying bacteria. This allows Matrix™, unlike other forms of biomedia, to remove nitrate along with ammonia and nitrite, simultaneously and in the same filter. "http://www.seachem.com/Products/prod...es/Matrix.html

I just looked up the matrix product description on seachem's website, and they claim:

"...These macropores are ideally sized for the support of nitrifying and denitrifying bacteria. This allows Matrix™, unlike other forms of biomedia, to remove nitrate along with ammonia and nitrite, simultaneously and in the same filter. "http://www.seachem.com/Products/prod...es/Matrix.html

Its possible. There is anoxic zones in the media. Where there is deplete of oxygen, thus allowing anaerobic bacteria to grow. Aerobic bacteria ( not sure how to spell ) will be on the outer side of the pores, consuming oxygen. That is why deep inside the pores, there is lack of oxygen.

I'm hesitant to point this out, as I have no interest in starting another argument about the necessity of bio-media, but because nobody has mentioned it (or I missed it), and cost seems to be a factor in this thread...

Many of us have gone the route of zero bio-media and have perfectly happy plants and fish. While there are a couple valid reasons to use bio-media in a filter, there's plenty of surface area for bacteria to colonize on without adding volcanic rock to the filtration process. Remember, also, that mech-media is *also* bio-media, without exception. Adding bio-media will not increase the amount of beneficial bacteria in the system. It will only provide an area of higher concentration of bb.

Again, there are a couple valid arguments for bio-media, and there are similarly valid arguments to the contrary. Good luck with whatever you decide!

Its possible. There is anoxic zones in the media. Where there is deplete of oxygen, thus allowing anaerobic bacteria to grow. Aerobic bacteria ( not sure how to spell ) will be on the outer side of the pores, consuming oxygen. That is why deep inside the pores, there is lack of oxygen.

Yes, I was thinking the same thing; somehow, the media must create localized anaerobic spots for denitrification to occur.

However, what would be the purpose (if anaerobic bacteria truly are present)? Denitrification would take the nitrates that are produced by the aerobic bacteria, and convert back to nitrites...which are then converted back to nitrates by the aerobic bacteria.

On top of this, the aerobic bacteria would be much in excess compared to the anaerobic bacteria, meaning nitrification would be very favoured.

This whole pumice talk made me research its debate the last couple days, and I can't find any evidence it'd the same as matrix. There's a lot of suspect it is, and a lot of visual similarity's but if you put it under a microscope it is different. No one really has a technical true answer to what it really is from my readings.

This whole pumice talk made me research its debate the last couple days, and I can't find any evidence it'd the same as matrix. There's a lot of suspect it is, and a lot of visual similarity's but if you put it under a microscope it is different. No one really has a technical true answer to what it really is from my readings.

totally agree with you although it looks similar , it doesnt mean it is the exact same .

To further fuel this discussion currently in my FX5 from top to bottom I have filter floss (walmart quilt batting), ring two (Pumice- BBQ grill scrubbers broken into inch pieces) ring three same as ring two. This same set up I use on my fluval 205 for my 29 gallon. I run zero chem and when i clean the filters I rinse tray two one month then tray 3 the following. BBQ scrubbers are 100% pumice, little dusty but a whole box of them i believe was like 10 bucks and filled one whole tray in my FX5.
But to field the question about zero oxygen zones, I would say that since pumice and matrix has pores that pass completely through it, wouldn't it require collection of debris on both sides of the pore to creat this dead zone?

CrypticLifestyle, I will find that answer out for you tomorrow night in my Chemlab class, I will take one piece of Matrix and one BBq scrubber into lab class with me and examine it and hopefully photograph it adnd I will post the findings here, I might be able to get some grad students to chem analize it for us too.

Yes, I was thinking the same thing; somehow, the media must create localized anaerobic spots for denitrification to occur.

However, what would be the purpose (if anaerobic bacteria truly are present)? Denitrification would take the nitrates that are produced by the aerobic bacteria, and convert back to nitrites...which are then converted back to nitrates by the aerobic bacteria.

On top of this, the aerobic bacteria would be much in excess compared to the anaerobic bacteria, meaning nitrification would be very favoured.

I think, and I'm not an expert by any means, the actual process in denitrification involves bacteria reducing nitrates to nitrites, and then reducing that to two things; nitrogen gas and ammonia. The part that's converted back to ammonia will get used again by the bb, but the part turned into nitrogen gas is not usable and is lost to the atmosphere.

CrypticLifestyle, I will find that answer out for you tomorrow night in my Chemlab class, I will take one piece of Matrix and one BBq scrubber into lab class with me and examine it and hopefully photograph it adnd I will post the findings here, I might be able to get some grad students to chem analize it for us too.

I'll be waiting for mass spectrometry results then. But seriously, I don't think you'll find many helpful graduate students, trust me, I know from experience. I was one of them

Quote:

Originally Posted by exv152

I think, and I'm not an expert by any means, the actual process in denitrification involves bacteria reducing nitrates to nitrites, and then reducing that to two things; nitrogen gas and ammonia. The part that's converted back to ammonia will get used again by the bb, but the part turned into nitrogen gas is not usable and is lost to the atmosphere.

Neither am I, my research had nothing to do with soil bacteria

A quick search on Pubmed reveals that denitrification generally involves bacteria reducing nitrates to nitrogen through the nitrite intermediary. There are some bacteria that just leave it at the nitrite step (meaning it would be available for beneficial bacteria), while some take it all the way to nitrogen gas.

While direct reduction to ammonium from nitrates is possible, apparently it is rarer than going through the nitrite intermediate.

I still find it hard to believe that an anaerobic environment could exist in a canister filter with good flow and porous media. Now, if it were a plenum, I could see it happening.

Register Now

In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:

Password

Please enter a password for your user account. Note that passwords are case-sensitive.

Password:

Confirm Password:

Email Address

Please enter a valid email address for yourself.

Email Address:

Log-in

User Name

Remember Me?

Password

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.